RAPD marker = dominant character marker?

I am an undergraduate students in Bandung. I have a several question that
maybe someone out there can answer. . .
- RAPD marker is said to be dominant-character marker. Alleles which
produces (dominant) bands to alelles which doesn't. If it so, why only
the dominant alelles are amplified?
- In sequencing, DMSO is used tome the reaction more efficient and faster.
Why is it so?
- Does anyone know Williams's e-mail address?
(William J.C.K; the one who founded the RAPD method)
Thanks.